Hello, I am fairly certain I just killed two DCC trains. They are dead on the main line and test track. Other trains will work on the test track and I am too fearful to put them on the layout. Could I have caused the short by placing Proses track voltage tester across a turnout's 3 rail lead (yeah, I'm on a 2 rail HO)? Or did the short happen because that same turnout happens to be a reverse loop (it has insulated connectors) but the trains always stopped at that point? I ran them over the area A LOT to determine where the power loss was happening.  Recommendations on how to fix this? And are my trains permanently goner's?

Thanks- I'm so sad by all this! But I am really trying to learn as much as I can!